Do you want change with that?
The bill for my order came to some number of dollars and four cents. I provided the server with a twenty and a nickel. She stared at it for a few seconds, fumbled with the coin dispenser for a few more, then hesitantly started counting out quarters and dimes, apparently talking to herself as she did so. Then she stopped and did an amazing job of looking simultaneously thoughtful and clueless.
I helpfully broke the uncomfortable silence by asking "It was [mumble] dollars and four cents, right?" She looked closely at the receipt, finally answering "Yeah." So I stated the obvious: "I gave you twenty dollars and five cents. So I should get back [mumble] dollars and a penny." She frowned in concentration for a few more seconds before apparently giving up and deciding to trust me, but she didn't seem convinced. After she gave me the change I was due, she skated away still looking unsure of what had just happened.
I wonder if she's usually good at making change for round numbers of dollars, and I just stunned her out of her mathematical comfort zone with my helpful inclusion of a nickel. Or maybe she was just used to people telling her to keep the change.
